Currently, a new version of QGIS is released around every four months. The version released each spring is designated as a long-term release (LTR). This means it will be supported for one calendar year. Each quarter, a new stable version is released and bug fixes applied to the LTR. The LTR is recommended for production environments since it has a slower release cycle. At the time of writing, QGIS 3.4.5 is the current LTR, with version 3.6 available for download.

QGIS can be installed on Windows, macOS, Unix, Linux, and Android operating systems, making it a very flexible software package. Both the binary installers and source code can be downloaded from download.qgis.org. In this section, we will briefly cover how to install QGIS on Windows, macOS, and Ubuntu Linux. For the most up-to-date installation instructions, refer to the QGIS website.

On the QGIS website, download the correct version of QGIS for your Windows machine. Downloadable executable files come in 32-bit and 64-bit flavors. We recommend downloading the latest release as advertised on the QGIS website download page. 

For Windows, there are two installation...

With the release of version 3 of QGIS comes a host of new features and tools—far too many to document here, but if you are interested, take a look at http://changelog.qgis.org/en/qgis/version/3.4-LTR. For the new addition to QGIS 3.6, have a look at this http://changelog.qgis.org/en/qgis/version/3.6.0/. The biggest shift in QGIS 3.x is the migration from Python 2 to 3, which has extended the functionality to run scripts, processes, and tasks. Further to this, the underlying application used to build the QGIS interface, called Qt as of version 3.x, runs off Qt5.

To highlight perhaps just a few of these new features, note the following:

• Data Source Manager: The Data Source Manager (accessed via  or Ctrl + L) is perhaps the most notable visual change of 3.4, as it is presented as the default tool to accessing data to load onto the Map...

QGIS is composed of two programs: QGIS Desktop and QGIS Browser. Desktop is used for managing, displaying, analyzing, and styling data. Browser is used for managing and previewing data. This section will give you a brief tour of the graphical user interface components of both QGIS Desktop and QGIS Browser.

The QGIS interface is divided into four interface types: Menu Bar, Toolbars, Panel, and Map Canvas. The following screenshot shows QGIS Desktop with all four interface types displayed:

The Map Canvas shows the styled data added to the QGIS project. The Menu Bar, displayed across the top, provides access to most of the QGIS functions. The Toolbars provide quick access...

When working with spatial data, it is important that a CRS is assigned to the data and the QGIS project. To view the CRS for the QGIS project, click on Properties under Project, and choose the CRS tab.

It is recommended that all data added to a QGIS project be projected into the same CRS as the QGIS project. However, if this is not possible or convenient, QGIS can project layers on the fly to the project's CRS.

To view the CRS for a layer, perform the...

There are two types of tables you can work with in QGIS: attribute tables and standalone tables. Whether they are from a database or associated with a shapefile or a flat file, they are all treated the same. Standalone tables can be added by clicking on Layer | Add Layer | Add Vector Layer.

QGIS supports the table formats supported by OGR along with database tables. Tables are treated like any other GIS layer; they simply have no geometry. Both types of tables can be opened within Desktop by selecting the layer/table in the Layers panel, and then by either clicking on Open Attribute Table under Layer, or by right-clicking on the data layer, and choosing Open Attribute Table from the context menu. They can also be previewed in QGIS Browser by choosing the Attributes tab.

The table opens in a new window that displays the number of table rows and selected...

Vector data layers can be edited within QGIS Desktop. Editing allows you to add, delete, and modify features in vector datasets. The first step is to put the dataset into edit mode. Select the layer in the Layers panel and click on Toggle Editing under Layer. Alternatively, you can right-click on a layer in the Layers panel and choose Toggle Editing from the context menu. Multiple layers can be edited at a time. The layer currently being edited is the one selected in the Layers panel. Once you are in edit mode, the digitizing toolbar (shown in the following screenshot) can be used to add, delete, and modify features:

From left to right, the tools in the digitizing toolbar are as follows:

• The Current Edits tool allows you to manage your editing session. Here, you can save and roll back edits for one or more selected layers.
• The Toggle Editing tool provides an additional...

With QGIS, you can create maps that can be printed or exported to image and graphic files. Prior to version 3, in order to create maps, you used the Print Composer; this has now changed its name to Layouts. To create a new Layout, click on Project | New Print Layouts. Give the new layout a name, click on OK, and the composer window will open. From this point on, you can access the new layout from Project | Layouts.

The composer presents you with a blank sheet of paper upon which you can craft your map. Along the left-hand side, there are a series of tools on the Composer Items toolbar. The lower portion of the toolbar contains buttons for adding map elements to your map. These include the map body, images, text, a legend, a scale bar, graphic shapes, arrows, attribute tables, and HTML frames. Map elements become graphics on the composition canvas. By selecting a...

There are so many potential workflows, analysis settings, and datasets within the broad field of GIS that no out-of-the-box software could contain the tools for every scenario. Fortunately, QGIS has been developed with a plugin architecture. Plugins are add-ons to QGIS that provide additional functionality. Some are written by the core QGIS development team, and others are written by QGIS users.

You can explore the QGIS plugin ecosystem by navigating to Plugins | Manage and Install Plugins. This opens the Plugins Manager window (shown in the following screenshot), which will allow you to browse all plugins, those that are installed, those that are not installed, plugins that are newly available, and adjust the plugin manager settings. If there...

This chapter provided a refresher on the basics of QGIS and a look at some of the new functionality of 3.x. We covered how to install the software on several platforms. We then covered how to load vector, raster, and database data layers. Next, you were shown how to work with coordinate reference systems and style data. We covered the basics of working with tables, including how to perform a table join. The chapter concluded with a refresher on composing maps, how to find, install, and manage plugins, and a primer on QGIS custom variables.

The next chapter will cover styling vectors and raster data. Now that you have had a refresher on the basics of QGIS, it is time to learn how to expand your work to include spatial databases. In Chapter 3, Creating Spatial Databases, you will learn how to create and manage spatial databases within QGIS.